EP 1148632 A3 20030129 - FM stereo signal demodulating apparatus
Title (en)
FM stereo signal demodulating apparatus
Title (de)
Vorrichtung zum Demodulieren eines FM Stereosignals
Title (fr)
Dispositif de démodulation d'un signal FM stéréo
Publication
Application
Priority
JP 2000099765 A 20000331
Abstract (en)
[origin: US2001026621A1] An FM stereo signal demodulating apparatus includes a bandpass filter 1 for extracting a 19 Hz signal from an FM detected signal; a first phase shifter 21 for phase-shifting the 19 Hz signal by 90 degree; a first XOR 22 for taking an exclusive OR between an output from the first phase-shifter 21 and the 19 KHz signal; a second phase shifter 23 for phase-shifting an output signal from said XOR 21; a second XOR 24 for taking an exclusive OR between an output from the first XOR 22 and an output from the second phase shifter; an inverter 25 for inverting an output from said XOR 24; a third phase-shifter for phase-shifting an output signal from said inverter 25; a third XOR for taking an exclusive OR between an output from said third phase-shifter 26 and an output from said first XOR 22; a first multiplier 3 for multiplying an output from said first XOR 22 and said FM detected signal; a second multiplier 4 for multiplying an output from said third XOR 27 and said FM detected signal; a third multiplier 5 for multiplying an output from said second multiplier 4 by {square root}{square root over (2)}-1; a first adder 6 for adding an output from said first multiplier 3 and an output from said third multiplier 5; a second adder for adding said FM detected signal and an output from said first adder 6; and a subtracter 8 for subtracting an output from said first adder 6 from said FM detected signal. In this configuration, the FM stereo demodulating apparatus can operate as a low speed.
IPC 1-7
IPC 8 full level
H04B 1/16 (2006.01); H04H 5/00 (2006.01); H04H 40/45 (2008.01); H04L 27/144 (2006.01)
IPC 8 main group level
H04H 1/00 (2006.01)
CPC (source: EP US)
H04B 1/1646 (2013.01 - EP US); H04H 20/48 (2013.01 - EP US)
Citation (search report)
- [A] US 4506376 A 19850319 - NOGUCHI TADASHI [JP]
- [A] US 5442709 A 19950815 - VOGT LOTHAR [DE], et al
- [X] PATENT ABSTRACTS OF JAPAN vol. 013, no. 181 (E - 750) 27 April 1989 (1989-04-27)
- [A] PATENT ABSTRACTS OF JAPAN vol. 013, no. 181 (E - 750) 27 April 1989 (1989-04-27)
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR
DOCDB simple family (publication)
US 2001026621 A1 20011004; US 6714651 B2 20040330; EP 1148632 A2 20011024; EP 1148632 A3 20030129; JP 2001285226 A 20011012
DOCDB simple family (application)
US 82248401 A 20010402; EP 01108196 A 20010330; JP 2000099765 A 20000331